Self-drilling tie rod for concrete construction forms



June 27, 1957 w, c. BZFHDGES 3,327,988

SELF-DRILLING TIE ROD FOR CONCRETE CONSTRUCTION FORMS Filed Nov. 27,.1964

INVENTOR. WILLIAM C. BRIDGES I BY 8- H-S U ATTORNEY United States Patent3,327,988 SELF-DRILLING TIE ROD FOR CONCRETE CONSTRUCTION FORMS WilliamC. Bridges, 3551 NW. 97th St, Miami, Fla. 33147 Filed Nov. 27, 1964,Ser. No. 414,301 2 Claims. (Cl. 249-213) My invention relates toconcrete beam column and lintel construction, and is directedparticularly to a novel and improved tie rod for setting up forms forsuch concrete construction.

It is a common practice when building with poured concrete to hold theside walls of the form together in spaced relation by means of elongatedmetal tie rods extending transversely through aligned holes drilled inthe forms and secured in place at the outsides by fasteners such as nutsthreaded on the outer ends of the rods over washers or the like toprevent spreading of the forms under the weight of the wet concrete whenpoured. When the concrete has set, the side nuts or other fasteningmeans are removed and the projecting ends of the tie rod are broken off.It will be apparent that in using such tie rods, the labor involved indrilling the form holes and then setting and securing the tie rods inplace and thereafter removing them constitutes a large item in theoverall expense of the concrete forming. In construction jobs havingmany poured concrete lintels, beams and/ or columns, the labor involvedand time consumed in the setting up and removal of concrete forms withordinary tie rods as heretofore known can become disproportionatelygreat enough to slow down job progress or require the temporary hiringof additional workers.

It is accordingly the principal object of my invention to provide animproved tie rod for formed concrete construction the use of whicheliminates much of the labor involved in its placement, securement andremoval, thereby overcoming for the most part, the above-describeddeficiencies characteristic of tie rods heretofore devised.

A more particular object is to provide a tie rod of the characterdescribed comprising a rod member that is designed to be used as a drillfor simultaneously boring its form holes and positioning itself in placefor anchoring.

Another object is to provide a tie rod of the above nature includingnovel push-on anchors or fasteners for securing the outer ends of therod with respect to the form sides, which fasteners operate inconjunction with spaced annular grooves formed along the length of therod, and wherein the grooves provide means for locking the forms inspread relation against the rod fasteners and also provide zones ofweakness along the length of the rod ends facilitating breaking offclose to the sides of the formed and hardened concrete after removal ofthe forms.

Still another object is to provide a tie rod for poured concrete formingthat is readily adjustable over a wide range of widths commonly used inbuilding construction.

Yet another object is to provide a tie rod of the above nature whichwill be inexpensive to manufacture, reuseable in part, easy to installand remove, and effective and dependable in use.

Other objects, features and advantages of the invention will be apparentfrom the following description when read with reference to theaccompanying drawings. In the drawings, wherein like reference numeralsdenote corresponding parts throughout the several views:

FIG. 1 is a vertical section taken through a concrete structure andforms, showing a tie rod embodying the invention in place therein;

FIG. 2 is an end view of the tie rod drill point;

FIG. 3 is a vertical cross-sectional view taken along the line 3-3 ofFIG. 1 and illustrating constructional details of the fastener member;

Patented June 27, 1967 FIG. 4 is a vertical cross-sectional view takenalong the line 4-4 of FIG. 3; and

FIG. 5 is a plan view of one of the U-shaped washers used on the rod forholding the form boards in fully spread relation.

Referring now in detail to the drawings, 10 in FIG. 1 designatesgenerally a self-drilling tie rod assembly, embodying the inventionshown in place between parallel plywood form boards F, braced by walesor walers W running along the outsides thereof. The tie rod assembly 10comprises an elongated rod member 11, fastener members 12 and U-shapedwashers 13. The rod member 11, which is preferably of steel, is forgedor otherwise formed along a central part of its length with annulargrooves 14 of about A inch in width and /;;g inch in depth equidistantlyspaced about /s inch apart. One end of the rod member 11 is providedwith a simple drill point 15, which may be substantially conical inform, as indicated at 15a, except for being hollowed out at one side, asindicated at 15b to provide cutting edges and relief means for thecuttings.

The fastener member 12 is preferably formed of sheet steel stock andcomprises a tubular body portion 16 flared outwardly at one end andterminating in an inwardlyturned peripheral base portion 17. The otherend of the fastener member body portion 16 is formed with a plurality,four in the illustrated embodiment, of axially-extending,peripherally-spaced elongated slots 18 defining resilient,outwardly-extending tongues 19, the terminal ends of which are bentinwardly at an angle inclining them slightly to the outside to providegripping teeth 20. The inner edges of the teeth 20 define a circle thediameter of which is somewhat less than the diameter of the elongatedrod member 11, so that said teeth will spring into the annular grooves14 of said rod member when assembled thereto as hereinbelow described.The fastener member 12 is provided with a nail hole 21 in its outwardlyflared end adjacent the base portion 17.

In use, after the form boards F and walers W are erected in the usualway, the rod member 11 will be chucked in a power drill and used todrill itself in place, as indicated in FIG. 1. The drill will then beremoved and a fastener member 12 placed over the projecting end of therod member and pushed in place against the adjacent waler W. Asillustrated in FIG. 3, the outward inclination of the gripping teeth 20of the fastener member, and their resiliency, will permit their beingreadily pushed inwardly over the outer diameter portions of the rodmember between the annular grooves 14 until the base portion 17 seatsagainst the outside of the waler W. Thereafter, any outward movement ofthe waler with respect to the rod member will cause the fastener teethto wedge into the outer corner of the nearest annular groove 14, asillustrated in FIG. 3, and thereby securely grip the rod. The Workmancan now place a nail N through the fastener nail hole 21 to temporarilyhold the fastener in place while he goes around to the other side of theform assembly to place a second fastener member 12 on the drill pointend of the rod member to complete the tie rod installation. Washers 13which have openings permitting a sliding fit within the rod membergrooves 14, can then be placed in the rod grooves adjacent the insidesof the form boards F, as illustrated in FIG. 1, to keep the form frombowing inwardly. It will be noted that the entire installation of thetie rod assembly can be made by one workman, or other than by twoworking one at each side of the form assembly.

After the concrete has been poured and hardened, and the forms are to beremoved, the projecting ends of the rod member can either be bent ortwisted off with a suitable wrench or the like, the break taking placeat the zone of Weakness provided by the rod groove 14 closest to theoutside, or usually just inside, the side wall of the formed concrete.In most instances the fastener member 12 will not be damaged in theremoval process, so that they can be saved for reuse, thereby effectingeven greater economy.

While the elongated rod member 11 is shown and described herein ashaving a continuous series of annular grooves 14, the grooves in thecentral portion of the rod could be omitted for a space no greater thanthe least thickness of formed concrete with which the tie rod is to beused. As the length can also be made to accommodate the greatestthickness of concrete likely to be formed, it will be understood thatone size of tie rod according to the invention can be used with a widerange of form board spacings.

While I have illustrated and described herein only one form in which myinvention can conveniently be embodied in practice, it is to beunderstood that this form is given by way of example only, and not in alimiting sense. My invention, in brief, comprises all the embodimentsand modifications coming within the scope and spirit of the followingclaims.

What I claim as new and desire to obtain by Letters Patent is:

1. In a tie rod for concrete construction forms, the combinationcomprising, an elongated rod, a plurality of closely'spaced annulargrooves formed along a central portion of said rod, a drill point at oneend of said rod, fastener members received circumjacently over oppositeend portions of said rod, means including said annular grooves forpreventing withdrawal of said fastener members from said ends of saidrods once placed thereon, said withdrawal preventing means comprising aplurality of substantially axially-extending, circularly-arranged, re-

silient tongue members formed on said fastener members, the outer endsof said tongue members having inwardlyinclined teeth the terminal edgesof which define a circle the diameter of which is less than the diameterof said elongated rod.

2. In a tie rod for concrete construction forms, an elongated rod ofsubstantially circular cross-sectional diameter, said rod having along acentral part thereof a plurality of equidistantly-spaced grooves, adrill point formed at one end of said rod, a fastener member for eachend of said rod, each fastener member comprising a tubular shell portionoutwardly flared from one end to the other, said other end of saidtubular shell portion having an inwardly-turned peripheral end portiondefining a circular base, said one end of said tubular shell portionbeing of small diameter as compared with said base and being formed witha plurality of peripheral, substantially axially-extending resilienttongue members, the inner ends of said tongue member being integrallyformed with inwardly-inclined teeth, the inner edges of said teethdefining a circle the diameter of which is less than the diameter ofsaid rod.

References Cited UNITED STATES PATENTS 913,538 2/1909 Morgan. 1,293,3912/1919 Ewing 249-214 2,293,743 11/ 1940 Miles et a1. 2,321,157 6/1943Rees 85-36 2,336,153 12/1943 Ryder. 3,263,958 8/1966 Cox et al 249213 1.SPENCER OVERHOLSER, Primary Examiner.

1. IN A TIE ROD FOR CONCRETE CONSTRUCTION FORMS, THE COMBINATIONCOMPRISING, AN ELONGATED ROD, A PLURALITY OF CLOSELY-SPACED ANNULARGROOVES FORMED ALONG A CENTRAL PORTION OF SAID ROD, A DRILL POINT AT ONEEND OF SAID ROD, FASTENER MEMBERS RECEIVED CIRCUMJACENTLY OVER OPPOSITEEND PORTIONS OF SAID ROD, MEANS INCLUDING SAID ANNULAR GROOVES FORPREVENTING WITHDRAWAL OF SAID FASTENER MEMBERS FROM SAID ENDS OF SAIDRODS ONCE PLACED THEREON, SAID WITHDRAWAL PREVENTING MEANS COMPRISING APLURALITY OF SUBSTANTIALLY AXIALLY-EXTENDING, CIRCULARLY-ARRANGED,RESILIENT TONGUE MEMBERS FORMED ON SAID FASTENER MEMBERS, THE OUTER ENDSOF SAID TONGUE MEMBERS HAVING INWARDLYINCLINED TEETH THE TERMINAL EDGESOF WHICH DEFINE A CIRCLE THE DIAMTER OF WHICH IS LESS THAN THE DIAMETEROF SAID ELONGATED ROD.